Is 0x allowed?

Could you elaborate on the context in which you're asking if "0x" is allowed? If we're discussing cryptocurrency exchanges or wallets, "0x" typically refers to the protocol that enables decentralized exchange of Ethereum-based tokens. In that sense, many exchanges and wallets do support 0x and its native token, ZRX, for trading and storage. However, if you're referring to a specific platform, service, or regulatory environment, the answer may vary. Could you clarify the context so I can provide a more accurate response? Additionally, if there are any specific regulations or policies you're concerned about, I can address those specifically as well.